Froth flotation of sulphide ores



Patented Dec. 10, 1946 STATES PATENT orriics Fao'rn r Lora'ngii 'fi sutrmns once I Arthur H. Fischer, New York, N. Y.

No Drawing. I Application April 21, 1944, Serial N0. 5.2305

1: This invention-relates to th concentration of ores-and has for an object the provision of certain improvements in concentration operations. More particularly, the invention contemplates the provision Qfrcertain improvements in flotation operations; A further object of the invention is to provide certain improvements in flotation methods or processes. I

The invention is based on my discovery that alkyi xanthogen formates which are unsymmetricalwithrespect to the alkyl radicals are highly efiective flotation reagents which may be employed advantageously as mineral collecting agents in" conjunction with frothing agents and conditioning agents in froth flotation operations. Ali ylxanthogen fcrmates found most suitable for-use in flotation concentration processes are those in which the larger alkyl radicals are disposed on the xanthogen side as indicated by the I following structural formula:

s o nodes-lion in which R and R. are alkyl radicals and R contains the greater numberof carbon atoms.

I have found that the alkyl xanthogen f ormates which are unsymmetrical with respect to the alkyl radicals may be employed more advantageously in various flotation circuits than those which are symmetrical. Thus, for example, a symmetrical compound comprising relatively small alkyl radicals, such as ethyl xanthogen ethyl formate, tends to break down and become ineffective in an alkaline circuit. Compounds having larger alkyl radicals substituted for or instead of one or both of the ethyl radicals have greater stability in alkaline circuits. A compound having the same larger radical substituted for or instead of the ethyl radicals on both the xanthogen side and the formats side may be of such stability as to be practically ineffective as a flotation agent. A compound having a larger radical on only the xanthogen side has desired stability without decreased flotative properties. I have found that a compound comprising on the Xanthogen side an alkyl radical containing five or more carbon atoms and comprising on the formate side an alkyl radical containing alesser number of carbon atoms generally may be employed with great advantage as a notation agent.

.' of both oxidized ores and sulphide ores.

' ethyl radical.

6' Claims. (or. 209-106) Among the compounds found to be most efiecr' tiveare those comprising on the xanthogen side alkyl radicals containing-five or morecarbon atoms and comprising on the formate side the.- Bpecii'ic compounds whlchhave been foundto be highly effective include amyl; xanthogen ethyl formate and hexyl xanthogen; ethyl formate. V V

In practicing a method or process of the invention, a neutral, acid or alkaline circuit may be employed. The flotation reagents may be emplayed with particular advantage in alkaline .circults. J The flotation reagents may be employed advantageously in froth flotation operations designed for the concentration of both non-metallic minerals and metallic minerals and in froth flotation operations designed for the concentration The. reagents can be employed with partlcular advantage in froth'flotation operations designed for the concentration of copper sulphide ores and other sulphide ores.

The following examples lllustratetthe advantages of, the reagents andprocesses of the invention over reagents and processes employed heretofore.

Example I Humbolt copper sulphide ore of the following composition with respect to copper was ground in water to form three separate aqueous pulps which were subjected to separate froth flotation operations in the presence of the reagents indicated with the production of concentrates and tailing products of the analyses indicated:

in water to form two separate aqueous pulps which were subjected to separate froth flotation operations in the presence of the reagents indiin water to form three separate aqueous pulps which were subjected to separate froth flotation operations in the presence of the reagents indicated with the production of concentrates and tailing products of the analyses indicated:

cated with the production of concentrates and tailing products of the analyses indicated: 1 2 a Test Heads percent Cu Concentrates percent Cu. 1 2 Tails percent Cu Holds percent Ou 12 1 12 v REAGENTS, POUNDS PER TON Concentrates percent Cu. 16.84 16.48 15 silspercent Cu .68 .18 Lime n 8 8 8 Pine oil REAGENTB, POUNDS PER TON Ethyl mnthosen ethyl ro mate Amy] xauthogen amyl formate Amyl xanthogen ethyl formate Lime 12 12 2o Plneoll .14 .14 Ethyl xanthogen ethyl fol-mate .02 Iclaim: Amylmmgen hymrmate 1. The method of concentrating sulphide ore which comprises subjecting the ore in the form Example III of a pulp to a froth flotation operation in the Heads percent Cu Concentrates gercent Cu Tails percent u Ethyl starters-5555mm; Hexyl xanthogen ethyl iormate Example IV presence of amyl xanthogn ethyl formats.

2. The method of concentrating sulphide ore which comprises subjecting the ore in the form of a pulp to a froth flotation operation in the presence of hexyl xanthogen ethyl formate.

3. The method of concentrating copper suiphide ore which comprises subjecting the ore in the form of a pulp to a froth flotation operation in the presence of amyl xanthogen ethyl formate.

4. The method of concentrating copper sulphide ore which comprises subjecting the ore in the form of a pulp to a froth flotation operation in the presence of hexyl xanthogen ethyl formate.

5. The method of concentrating sulphide ore which comprises subjecting the ore in the form of a pulp to a froth flotation operation in the presence of a compound of the group consisting of amyl xanthogen ethyl formate and hexyl xanthogen ethyl formate.

6. The method of concentrating copper sulphide ore which comprises subjecting the ore in the form of a pulp to a froth flotation operatin sisting of amyi xanthogen ethyl formate and hexyl xanthogen ethyl formate.

ARTHUR H. FISCHER. 

